Cylinder-finishing tool



Nov. 20, 1923. 1 ,4 1,474,649 Y 4 A. STORM CYLINDER FINISHING TOOL Filed0C4; 30 H 1922 Patented Nov. 20 1923.

UNITED STATES ALOLPH STORM, OF MINNEAPOLIS, MINNESOTA, ASSIGNOR TO STORMMANUFACTUR ING COMPANY, OF MINNEAPOLIS, MINNESOTA, A COPARTNERSHIPGONSISTING OF SAID STORM AND O. W. NELSON.

CYLINDER-FINISHING TOOL.

Application filed October 30, 1922. Serial No. 597,866.

To all whom it may concern:

Be it knownv that I, ADOLPH STORM, a citizen of the United States,residing at Minneapolis. in the county of Hennepin and State ofMinnesota, have invented certain new and useful Improvements inCylinder-Finishin Tools; and I do hereby declare the fol owing to be afull, clear, and exact description of the invention, such as will enableothers skilled in the art-to which it appertains to make and use thesame.

My invention provides an improved and highly. efficientcylinder-finishing tool, and, generally stated, the invention consistsof the novel devices and combinations of devices hereinafter describedand defined in the claims.

This improved tool. herein designated as a cylinder-finishing tool, isadapted to be used to polish and finish'the cylindrical surfaces of newor rebored engine cylinders. In fact, the tool is adapted for use totrue up old cylinders without: requiring reboring where but little metalneeds to be removed.

The preferred form of the tool is illustrated in the accompanyingdrawings, wherein like characters indicate like parts throughout theseveral views.

Referring to the drawings: Fig. 1 is a side elevation of the improvedtool;

Fig. 2 shows the tool'chiefiy in section on the line 22 of Fig. 1, butwith some parts in full and with the tool applied in a cylinder; and

Fig. 3 is a horizontal section taken on the line 3 3 of Fig. 2.

The cylinder casting is indicated by the numeral 4. The finishin tool isadapted to be carried and rotate .by any suitable means,'but, as shown,is carried at the lower end of an upright rotary spindle 5. Said toolcomprises a head 6 into whicha trunnion on the lower end of the spindle5 is shown as axially screwed. Said head 6 has a large axial cylindricalcavity 7 and, below said cavity, has a diametrical slot 8. At itsextreme lower end, extending transversely and centrally of the slot 8,the head 6 is provided with a. transverse bridge 9. Pivoted n the bolts10 applied to opposite sides of the head (3 are downwardly diitsthreaded lower portion.

verging gripper-carrying levers .11. Each lever 11, as shown andpreferably designed. comprlses a pair of rigidly connected metal straps.the lower portions of which are spread to form forks 12. These forks 12embrace the sides of hone or grinding stone grippers 13 and,'at theirlower ends, are pivotally connected to the central portions thereof bynut-equipped bolts 14. These grippers 13 are preferably channel-shapedstamped metal structures, the sides of which are adapted to be sprungtogether by clamping bolts 15 and thereby firmly clamped to the hones orgrinding stones 16. As shown, the grippers 13 are provided withoutstanding centrally located. ears 17 that are connected by a lightcoiled spring 18, the function of which will presently appear.

Working with threaded engagement through the bridge 9 and extendingaxially of the head 6 into the cavity 7 thereof is an an 101 bolt 19, tothe upper end of which a flange 20, as shown in the form of a washer, isrigidly secured by a clamping nut 21. A disk-like follower 22 isslidahly mounted on the smooth portion of the bolt 19 and engages theshort lug-like upper end projections 23 of the levers 11. v

A coiled spring 24 loosely surrounds the bolt 19 and and is compressedbetween the relatively fixed flange 20 and slidable or loose follower22. This spring 24 is of such strength that it readily overcomes therelatively light tension of the spring 18 and normally holds the levers11 spread as ar as permitted by the engagement of the follower 22 with ashoulder 25 formed on the bolt 19 at the upper extremity of The extremelower threaded end of the bolt 19 is preferably formed with a transverseslot 26 adapting it to be readily turned by a screw driver;

Operation.

Normally or when the tool is outside of the cylinder, the main tension 5ring 24 will hold the follower 22 against t e shoulden 25, therebydetermining the normal spread of the outer grindingfaces of the twohones 16, but it is obvious that the farther the bolt 19 is screwed downthrough the bridge 9, the wider will be the spread of the tw hones underthe normal condition above just noted. In adjusting the tool for anyparticular cylinder, the bolt 19 should be set so that the follower 22will be slightly above the shoulder 25 when the hones are active againstthe inner surface of the cylinder. The spring 18 simply takes up slackand keeps the lugs 28 of the levers 11 lightly premed against thefollower 22, when not in use, but the tension of said spring 18 doesnot, in any case, interfere with the action of the spring 24, thefunction of which latter is to keep the hones pressed outward intoengagement with the cylinder under the propergri'nding tension.

lVith the bolt 19 set in a certain position, it is evident that thespring 24 will have increasing tension as the hones are moved closertogether-and, hence, that in the absence of a provision for adjustment,the bones would be forced against cylinders of ditferent sizes, underdifferent pressures. This is entirely avoided with the arrangementdescribed, for with the hones setinto any. particular cylinder, the bolt19 may 77 be t d axially so as to give exactly the desired pressure. It,of course, also follows that the spring 24 may be set under any desiredtension for any particular diameter of cylinder but may be constant inpressure for cylinders of different diameters This improved tool, byvirtue of the construction already described, has another and veryhighly important action which will now be fully considered.

It is evident that if one ofthe levers 11 be moved toward the axis ofrotation while the other lover remains in a more divergent position, thesaid first moved lever will be subject to the entire tension from thespring 24. From this, it follows that the two levers will be subject tothe same tension from the spring 24 when and only when the axis of theshaft 5 and head 6 is coincident with the axis of the cylinder intowhich the hones have been inserted. It, for instance, the said axis iscloser to the right-hand than to the left-hand side of the cylinder.then the spring 24 will exert a lateral thrust through the right-handlever 11, which will tend to move either the cylinder toward the rightor the shaft 5 and head 6 toward the left, until the axis of the tool iscoincident with the axis of the cylinder, and when the cylinder is freeto shift in respect to the head 6 or the said head 6 is free to shift inrespect to the cylinder, the accurate alignment of the tool with thecylinder will be automatically accomplished by the rotation of the toolwithin the cylinder.

The above self-centering action is highly important and, of course,would not be present with a spring, for example, having its basis ofreaction directly against or between the two levers.

In actual practice, the efficiency of this tool has been thoroughlyden'ionstratcd. The hones or grinding stones may be of any materialwhich will put an extremely smooth finish on 'the interior of thecylinder. In some cases, they inight even be coarse. for rapidlyremoving the interior surface of the cylinder, but usually they will beof fine grain for producing a fine finish.

The term hone is herein used in a broad and liberal sense to include,any kind of abrasive finishing or cutting block or the like. In themost approved arrangement of the tool, the head will be rotated whilethe cylinder being finished will be held against rotation, frictionally'or otherwise, but it would be within the scope of the invention asherein claimed to hold the finishing toolagainst rotation and to rotatethe cylinder.

What I claim is:

1. A tool of the kind described comprising a rotary head, levers pivotedto said head, finishing hones pivotallycarried by the extended endsof'said levers, a spring tension device carried by said head andindependently reacting against said levers and exert ing a force thereontending to spread said levers and finishing hones, said spring tensiondevice being adjustable as an entirety, so as to vary the spread of saidlevers without changing the tension of said spring tension device.

2. The structure defined. in claim 1 in further combination with meansfor adjusting the tension of said spring tension device independently ofits ad ustments as an entirety.

3. A tool of the kind described comprising a rotary head, levers pivotedthereto, finishing hones pivotally carried by the extended ends of saidlevers, a spring tension device reacting against said head andindependently reacting against said levers and exerting a force thereontending to spread said levers and finishing hones, the said springtension device having a stop normally limiting the action on saidlevers, and means for adjust ing said stop and the base of reaction ofsaid spring tension device in respect to said levers.

4. A device of the kind described comprising a rotary head, a pluralityof levers pivoted to said head at their upper ends for swingingmovements in planes radiating from the axis of said head. said levei sat their pivoted upper ends having inwardly ofi'set bearing lugs, aspring-pressed follower seated lIl said head and independently operatingon the bearing lugs of said levers and exerting force tending to movesaid levers radially outward, and finishing tools pivoted to the freeends of said levers.

5. A device of the kind described comlilo prising a rotary head havingan axial cavity and below said cavity having diametrically and subjectto said spring and having a limited downward movement on said bolt, apair of levers pivoted to said headwithin the diametrically oppositeslots thereof and having upper ends independently engageable with saidspring-pressed follower, grippers intermediately pivoted to the lowerends of, said levers, and bones held by said grippers.

6. The structure defined in claim 5 in combination with a retractingspring connecting said grippers and exerting a .force thereon inopposition to but materially less than the said tension spring.

In testimonywhereofl aflix my si nature.

ADOLPH s 'r RM.

